番鸭呼肠孤病毒的分离与鉴定

从番鸭肝“白点病”患鸭的肝脾匀浆中分离到 7个病毒分离株 .在电镜下观察到病毒粒子呈球形 ,无囊膜 ,有可见的双层衣壳结构 ,外壳直径 75nm,内核直径 50 nm;病毒核酸型为 RNA;不凝集鸡、鸭、兔、豚鼠红细胞 ,与禽呼肠孤病毒有一定的抗原相关性 ;对番鸭胚和鸡胚成纤维细胞可致感染细胞圆缩、融合 ,出现多核细胞和巨细胞 ,胞浆内有近核包涵体 ;试验感染 1日龄敏感雏番鸭死亡率达 10 0 % ,临床及病理变化与自然感染发病的番鸭基本一致 ,并可回收到该病毒 .结果表明 ,目前国内流行的番鸭肝“白点病”病原为呼肠孤病毒科正呼肠孤病毒属番鸭呼肠孤病毒

Isolation and identification of Muscovy duck reovirus

Seven strains of reovirus were isolated from the liver and spleen with lots of gray white local necroses (“liver white spots”) of Muscovy duck. The virion showed spherical, no envelope, having double deck capsids, with outer capsid of 75 nm in diameter, with inner capsid of 50 nm in diameter; inagglutable red cells of chicken, duck, ribbit and gumea, it had certain antigen correlation with avian reovirus by AGP. The isolated B3 could produce some cytopathogenic effects such as the rounded cells, the fusion cells, polykaryocytes and megacells with inclusions in cytoplasm on the Muscovy duck or chicken embryo fibroblast cells. The mortality rate of the one day old sensitive Muscovy dusk inoculated with the isolated virus was up to 100%, and the clinical signs and the pathologies of died Muscovy duck were identical with those of field cases, and the isolated strain was recovered again. The results demonstrated that the pathogen of being epidemic liver “white spots” disease of domestic Muscovy duck was Muscovy duck reovirus, which was a member of the family Reoviridae, genus Orthoreovirus .